The present invention refers to a method for creating an atmosphere in an area which adjoins an outwardly open, inner portion of the body of a human being or an animal, comprising the step of supplying a gas to the area which gas forms a main component in said atmosphere. The invention also refers to a device for creating an atmosphere in an area which adjoins an outwardly open, inner portion of the body of a human being or an animal, which device comprises a gas supply member which is connectable to a gas source.
When an outwardly open portion arises on the body of a human being or an animal, the risk for infections due to bacteria or any other micro-organisms increases, which micro-organisms may easily penetrate the body because the protective skin is removed. Such open portions arise in connection with operations and other surgery operations and in the case of open wounds, which may have been caused by different injuries, accidents or diseases. In order to reduce this risk of infection one attempts, at least at hospitals, to keep the surrounding atmosphere and the skin as sterile as possible by filtering and cleaning, respectively, and by the use of different types of disinfectant. Of course it is important to close as quick as possible such open portions to prevent the penetration of bacteria.
Furthermore, in connection with operations tissues and vessels are exposed to air, the main components of which, i.e. nitrogen and oxygen, hardly dissolve in tissue. This results in an activation of a plurality of so-called cascade systems, inter alia within coagulation. Within vessel and heart surgery, the situation is more complicated by the fact that due to the opening of the vessels and the heart one can both actively and passively introduce air into the cavities of the vessels and the heart. Thereafter, it is very difficult to remove completely the air from the vessels and the heart merely by blood filling without air bubbles being further transported with the bloodstream, due to the fact that air mixed with blood gives bubbles similar to a foam. When the bubbles of air are transported with the bloodstream to the capillaries, the bubbles remain in the capillaries during some minutes, whereafter they are slowly absorbed or slowly pass the capillaries. The inside of the vessels, including the inside of the capillaries, is covered with endothelial, which is very depending on oxygen, i.e. depending on the oxygen bond in the blood, and a remaining air bubble in a small vessel or capillary results in an endothelium injury. Also when the bubble has been absorbed or transported further this activates and results in the injured endothelium wall being covered by white blood cells which in turn already can be ready to attach to the injured endothelium due to the so called operation trauma and/or the exposing to foreign material through for example the use of a heart-lung-machine. The result is an embolisation, i.e. a blocking of the vessel and the capillary of firstly the air bubble, which remains in the vessel during in the range of minutes, and secondly of white blood cells, which remain during a long time because of the following reaction between the injured endothelium and active white blood cells. Thereby, the area which is supported by the vessel and the capillary gets no blood support, whereby in particular oxygen depending tissue, especially the brain, is injured.
The object of the present invention is to create a desired atmosphere in connection with outwardly open body portions, such as in connection with surgery operations. In particular, according to a first aspect of the invention, it is aimed at the prevention of bacteria growth in such portions and according to a second aspect of the invention, it is aimed at a reduction of the problem of embolisation in connection with surgery operations, in particular vessel and heart surgery.
This object is obtained by the device initially defined and characterized in that said gas comprises a substantial amount of carbon dioxide.
Carbon dioxide has bacteriostatic/bactericidal properties and by creating an atmosphere of carbon dioxide in an area, which surrounds an open portion of the body, one may effectively prevent a bacterial growth in the open portion, for example a wound or a surgical cut. Moreover, the supplied carbon dioxide may be substantially completely sterile, i.e. the supplied gas comprises no micro-organisms or bacteria, and in this way bacteria or micro-organisms which exist in the surrounding air are prevented from reaching said area. The bacteria or micro-organisms which exist in the area or which for some reason would manage to penetrate the area can however not propagate themselves. Furthermore, one may by the supply of the carbon dioxide gas prevent the entrance of the surrounding air to an open area of the body in connection with an operation or a surgery operation. Consequently, air may not penetrate the bloodstream and cause the above discussed air embolisation. Carbon dioxide, which in relation to the main components in air, i.e. oxygen and nitrogen, has a high solubility in tissue, may be permitted to penetrate the open body portion because carbon dioxide is not going to create bubbles but rapidly be resorbed in the tissue and in this way embolisation and thereby blocking of small vessels and capillaries, may be avoided. Consequently, the carbon dioxide does not remain as bubbles in the blood vessels and will therefore not prevent the bloodstream in the same way as common air. Moreover, carbon dioxide is more heavy than air and therefore one may in a simple way create an atmosphere free from air in said area, since the more heavy carbon dioxide will pass downwardly into the open body portion and force away the air which exists down in this open portion. Furthermore, the carbon dioxide is substantially inert with regard to living organisms at least when it appears in moderate quantities.
According to a further embodiment of the invention, said gas is supplied to the area in a substantially continuous flow. In this way, it is possible to guarantee an atmosphere which is free from air in said area although some of the supplied gas leaves the area.
According to a further embodiment of the invention, said gas is supplied to the area in a substantially laminar flow. By such a laminar flow, it is possible to supply said gas in a controlled way and thereby it is also possible to avoid or at least substantially reduce the presence of turbulence in the area, which otherwise might result in the suction of air from the surrounding atmosphere into the area.
According to a further embodiment of the invention, the area is shielded off from the surrounding atmosphere in such a way that the supplied gas is kept within the area. By such a shielding off, the surrounding air is also prevented from penetrating the area, and consequently the maintaining of the atmosphere free from air is facilitated.
According to a further embodiment of the invention, a stream of said gas is supplied in a direction towards a part of said inner body portion. At least in some cases such a simple performing of the method, with only one or a few flow streams of said gas, is enough for keeping, within a limited area, the atmosphere substantially free from air.
According to a further embodiment of the invention, said gas is humidified before it is supplied to the area. In such a way, one may in an effective way reduce the evaporation from the open portion and consequently prevent dehydration.
The object is also obtained by the device initially defined and characterized by a gas source which comprises a gas with a substantial amount carbon dioxide and in that the gas supply member is arranged to supply said gas to said area in such a way that the carbon dioxide forms a main component in said atmosphere.
According to embodiments of the instant invention, the gas supply member may permit the supply of the gas to the area in a substantially continuous flow. The gas supply member may also comprise a nozzle which is arranged to supply the gas in a substantially laminar flow to the area. The gas supply member may further include a shield member, which is provided to be arranged around the area and to prevent the supplied gas from exiting the area. Further, the gas supply member may include several nozzle openings, which are arranged to direct a flow of the gas towards the center of the area. Also, the gas supply member may be configured so that nozzle openings are provided in a ring-shaped configuration, which is arranged to surround the area.
The object is also obtained by a use of carbon dioxide for the manufacture of a medicament to be supplied to an outwardly open inner portion of the body of a human being or an animal in order to create an atmosphere, which prevents growth of micro-organisms comprising bacteria and virus in said area. Furthermore, the object is obtained by a use of carbon dioxide for the manufacture of a medicament to be supplied to an outwardly open inner portion of the body of a human being or an animal in order to create an atmosphere, which prevents penetration of air into said area.